1. Field of the Invention
The present invention relates to optical sensors, more specifically to thermal management of optical sensors.
2. Brief Description of Related Art
One of the most difficult challenges posed by high resolution imaging equipment is management of the thermal output of the many electronic components, especially the large amount of localized energy generated by the required high density of focal plane arrays (FPAs). As technology advances, the power dissipated per FPA tends to increase, as well as the number of FPAs in each optical sensor. However, in order for optical sensors and their component FPAs to function properly, the environment must be maintained below a maximum temperature. Given the high number of FPAs and their dense packaging, thermal management continues to be an increasingly important and difficult aspect of high resolution imaging.
Traditional thermal management techniques use circulated cooling air and heat sinks, usually constructed of a suitable metal, to dissipate thermal energy generated by optical sensors. Most of the existing techniques for thermal management of high resolution imaging systems including composite focal plane arrays (CFPAs) use a structure comprising an interposer positioned between the printed circuit (PC) boards, wherein at least one outer edge of the interposer is capped by a semiconductor material, such as aluminum nitride. Typically, in these techniques, a heat sink is positioned adjacent to this end-cap, in a flow path of the circulating air. However, the thermal dissipation potential of these traditional techniques has largely been maximized, and modern imaging systems exceed even this maximized dissipation capability.